Glass cover for a vehicle roof and production method therefor

ABSTRACT

The invention relates to a glass cover ( 10 ) for a vehicle roof, comprising an at least partially transparent pane ( 14 ) of safety glass and optionally a support arrangement ( 18 ), which is mounted on the pane lower side in the pane edge area by means of a foam block ( 16 ) provided there. Said pane ( 14 ) is provided, on the lower side thereof, with a transparent composite film ( 26 ), which contains an adhesive film ( 28 ) and a tear- and scratch-resistant shatterproof film ( 30 ) as well as optionally embedded solar cells ( 62 ). According to the present invention, said shatterproof film ( 30 ) is bonded on the pane lower side by means of said adhesive film ( 28 ) in the center of the pane and incorporated into the foam block ( 16 )

[0001] This invention relates to a glass cover for a motor vehicle roofas claimed in the preamble of claim 1 and a process for producing thesame.

[0002] A glass cover which is provided in addition with solar cells asclaimed in the preamble of claim 1 is known for example from DE 43 23140 A1. A cover on the bottom is foamed into an enclosing frame with avery narrow edge area so that when the glass pane breaks the cover withthe glass fragments can fall into the vehicle interior.

[0003] The object of this invention is to devise a glass cover with orwithout a solar function for a motor vehicle roof which offersprotection as good as possible to the passengers and to the vehicleinterior when the glass cover breaks and is still easy to produce.Furthermore the corresponding production process will be devised.

[0004] This object is achieved as claimed in the invention by a glasscover with the features named in claim 1 and by a corresponding processas claimed in claim 14. In these approaches as claimed in the inventionit is advantageous that when the glass pane breaks on the one hand thefragments of the broken glass pane remain suspended on the protectivefilm composite and on the other hand in that the protective filmcomposite in the edge area is securely joined to the carrierarrangement, the protective film composite no longer being flexurallystiff, but like a collecting net which is securely clamped on the edges,being held in place in the cover. In this way the glass fragments can beprevented from reaching the vehicle interior, passengers can beprevented from being thrown through the broken glass to the outside,articles from the outside can be prevented from being able to penetratethrough the broken pane into the interior or the interior is preventedfrom being freely accessible when the glass pane is destroyed in case ofa burglary.

[0005] Preferred embodiments of the invention follow from the dependentclaims.

[0006] The invention is detailed below using the attached drawings byway of example.

[0007]FIG. 1 shows a section through the side edge area of the glasscover as claimed in the invention;

[0008]FIG. 2 shows a view of the film composite which is used in themanufacture of the cover;

[0009]FIG. 3 shows a section similar to FIG. 1 before cementing the filmcomposite on and peripheral foaming; and

[0010]FIG. 4 shows a view similar to FIG. 1, but an embodiment of aglass cover provided with solar cells being shown.

[0011]FIG. 1 shows a first embodiment of the glass cover 10 which isdesigned for closing or selectively clearing the opening in a fixed roofskin. It can be for example the cover of a sliding roof, sliding andlifting roof, raising roof or spoiler roof or also a fixed roof window.The glass cover 10 comprises a transparent glass pane 14 which in itsedge area is provided with peripheral foam 16 (for example, polyurethanefoam), by means of which preferably a carrier arrangement 18 made forexample as the inside cover sheet is attached in the edge area of thepane 14 to its bottom. The inside cover sheet 18 is used as a carrierarrangement for the glass pane 14 in order to join it to an adjustmentmechanism (not shown) for the cover 10. On the outside periphery of thefoam 16 there is a seal 20 to prevent penetration of moisture into thevehicle interior 22 with the cover 10 closed. Furthermore, in the edgearea of the pane 14 on the bottom in the area of the foam 16 or of theinside cover sheet 18 there is a glass filter in the form of printingwhich is used as nontransparent visual protection to cover theperipheral foam 16 and the inside cover sheet 18 from the top.

[0012] The glass pane 14 is made preferably from thermally prestressedsingle-pane safety glass.

[0013] In its central, transparent area the pane 14 on its bottom islaminated or cemented to a film composite 26, this central areaextending as far as the inner edge of the glass filter 24. The filmcomposite 26 is provided on its top, i.e. on the side facing the pane14, with an adhesive film or an adhesive layer 28 which is used tocement the underlying protective film 30 to the pane 14 in its centralarea. The protective film 30 is made to be tear-resistant andscratch-resistant. The film composite 26 with respect to its basesurface is smaller than the glass pane 14, but larger than its centraltransparent area.

[0014] The inside cover sheet 18 is foamed on the glass pane 14 by meansof the peripheral foam 16. In doing so the edge area 50 of the filmcomposite 26 which is provided with numerous perforations 52 is foamedinto the peripheral foam 16 at the same time. The foam mass passesthrough the perforations 52 and thus nondetachably embeds the filmcomposite 26 into the peripheral foam 16 by form-fit. Between the edgearea 50 and the area of the film composite 26 which is cemented to thecentral area of the pane 14 there is preferably a tension relief fold 42which among others prevents the cement connection of the film composite26 in the central area of the glass pane 14 from being exposed to atensile load by the attachment of the edge area 50 to the peripheralfoam 16 when the cover 10 is for example elastically deformed by theforces which occur in high speed driving. In this way the service lifeof the cover 10 can be increased.

[0015] Prior fixing or additional fixing of the edge area of the filmcomposite 26 can take place by means of a screw connection or in someother mechanical way, for example, by means of a clamp connection, tothe inside cover sheet 18.

[0016] The described construction is used to ensure that even when theglass pane 14 breaks a certain mechanical integrity of the cover 10 ismaintained by the film composite 26, even with the pane 14 broken,remaining clamped in its edge area 50 to the cover frame which is formedby the peripheral foam 16 and the inside cover sheet 18 and which isalso preserved with the glass pane broken. In doing so the filmcomposite 26 loses its flexural stiffness, but remains in the cover 10in place and can thus prevent on the one hand passengers from beingthrown to the outside through the broken pane 14 and on the other,fragments of the pane 14 or articles being able to penetrate from theoutside into the interior 22. Furthermore, the film composite 26provides for a certain burglary protection in the case of intentionaldestruction of the glass pane 14. The fragments of the broken glass pane14 remain suspended on the film composite 26 as a result of the adhesiveaction of the adhesive film 28.

[0017] As shown in FIG. 2, the adhesive film-free edge area 50 isprovided with perforations or openings 52 which are distributedessentially regularly over the edge area 50.

[0018] Proceeding from the state which is shown in FIG. 3, first thefilm composite 26 is cemented to the bottom of the pane in the centralarea of the glass pane 14 by means of the adhesive layer 28. Theadhesive film-free edge area 50 therefore is not joined to the glasspane 14. Then the glass pane 14 which is cemented to the film composite26 in this way is peripherally foamed in a conventional foaming toolwith a suitable material, for example polyurethane, in order to attachthe inside cover sheet 18 to the glass pane 14, the foam materialtravelling through the perforations 52. In this way the protective film30 is anchored in the peripheral foam 16.

[0019] In doing so, the anchoring of the protective film 30 can beadditionally reinforced by mechanical attachment of the edge area 50 ofthe film composite 26 on the inside cover sheet 18.

[0020] The adhesive film is preferably a polyvinylbutyral film (PVBfilm) or a transparent polyurethane film (PU film) while the protectivefilm 30 is preferably a plastic film which is coated to bescratch-proof, preferably a polyethylene terephthalate film (PET film)which is coated with polysiloxane.

[0021]FIG. 4 shows an embodiment in which the above described safetyconcept is applied to a solar cover, the bottom of the glass pane 14being provided with a solar cell film composite 60 which has a pluralityof solar cells 62 which are electrically interconnected and which arelocated between two hot-melt adhesive films 64 and 66, preferably ofethylene-vinyl acetate copolymer (EVA). The solar cell film composite 60is attached to the bottom of the glass pane 14 by means of the upperhot-melt adhesive film 64. The protective film composite 26 is attachedby means of the adhesive film 28 on the bottom hot-melt adhesive film 66to the solar cell film composite 60 and thus to the glass pane 14.

[0022] In the edge area 50 which is free of the adhesive film theprotective film composite 26 is anchored as in the embodiment shown inFIGS. 1 to 3 by means of the perforations 52 in the peripheral foam 16.Between the area which is anchored in the peripheral foam 16 and thearea of the protective film composite 26 cemented to the solar cell filmcomposite 60 there is a relief fold 42 to prevent delamination with thepane 14 intact as a result of tensile loading of the adhesive connectionbetween the protective film composite 26 and the solar cell filmcomposite 60 which could occur as a result of the anchoring of the area50 of the protective film composite 26 in the peripheral foam 16.

[0023] When the glass pane 14 breaks, the protective film composite 26which is anchored in the peripheral foam 16 prevents fragments of thepane and the solar cell film composite 60 from falling in and out andthus protects especially the vehicle interior and the vehiclepassengers.

[0024] In one modified embodiment the lower hot-melt adhesive film 66 ofthe solar cell film composite 60 can be omitted so that the adhesivefilm 28 of the protective film composite 26 is cemented directly to thesolar cells 62 or the upper hot-melt adhesive film 64 of the solar cellfilm composite 60.

[0025] Reference Number List

[0026]10 glass cover

[0027]14 glass pane

[0028]16 peripheral foam

[0029]18 carrier arrangement (inside cover sheet)

[0030]20 seal

[0031]22 vehicle interior

[0032]24 glass filter

[0033]26 film composite

[0034]28 adhesive film

[0035]30 protective film

[0036]42 relief fold

[0037]50 edge area (free of adhesive film) of 26

[0038]52 perforations in 50

[0039]60 solar cell film composite

[0040]62 solar cells

[0041]64,66 hot melt adhesive films of 60

1. Glass cover for a motor vehicle roof, with a pane (14) of safetyglass which is at least partially transparent, with a carrierarrangement (18) which is attached to the bottom of the pane (14) in theedge area of the pane (14) by means of peripheral foaming (16), with atransparent film composite (26) which is located on the bottom of thepane (14), which comprises an adhesive film (28) and a tear-resistantand scratch-resistant fragment protective film (30), the protective film(30) being cemented to the bottom of the pane (14) by means of theadhesive film in the central area of the pane (14) and in the edge areaof the pane (14) being foamed into the peripheral foam (16),characterized in that the film composite (26) in the edge area (50) isprovided with perforations (52) for passage of the foaming mass (16). 2.Glass cover as claimed in claim 1, wherein the edge area (50) of thefilm composite (26) is attached free of tensile stress with respect tothe cemented area by providing a relief fold (42) between the cementedarea and the edge area (50).
 3. Glass cover as claimed in claim 1 or 2,wherein the glass pane (14) in its edge area is made nontransparentespecially by a printed glass filter (24) and the peripheral foam (16),the carrier arrangement (18) and the edge area (50) of the filmcomposite (26) being located underneath the nontransparent area (24). 4.Glass cover as claimed in one of the preceding claims, wherein the edgearea (50) of the film composite (26) is not provided with an adhesivefilm (28).
 5. Glass cover as claimed in one of the preceding claims,wherein the adhesive film (28) is a polyvinylbutyral film (PVB film) ora polyurethane film (PU film).
 6. Glass cover as claimed in one of thepreceding claims, wherein the fragment protective film (30) is a plasticfilm which is coated with a scratch-proof enamel.
 7. Glass cover asclaimed in claim 7, wherein the fragment protective film (30) is apolyethylene terephthalate film (PET film).
 8. Glass cover as claimed inclaim 6 or 7, wherein the fragment protective film (30) is coated withpolysiloxane.
 9. Glass cover as claimed in one of the preceding claims,wherein the carrier arrangement is made as an inside cover sheet (18).10. Glass cover as claimed in one of the preceding claims, wherein thefilm composite (26) is attached to the carrier arrangement (18). 11.Glass cover as claimed in one of the preceding claims, wherein the pane(14) consists of single-pane safety glass.
 12. Glass cover as claimed inone of the preceding claims, wherein at least one solar cell (62) isintegrated into the film composite (26, 60).
 13. Glass cover as claimedin claim 12, wherein there is at least one hot-melt adhesive film (64,66), preferably of ethylene-vinyl acetate copolymer (EVA) for embeddingthe solar cell(s) (62) in the film composite (26, 60).
 14. Process forproducing a glass cover (10) for a motor vehicle roof, characterized bythe following process steps: Cementing a transparent film composite (26)which has an adhesive film (28) and a tear-resistant andscratch-resistant fragment protective film (30) in the central area onthe bottom of an at least partially transparent pane (14) of safetyglass by means of the adhesive film (28) which is provided in thiscentral area, Embedding of the edge area (50) which has a tear-resistantand scratch-resistant fragment protective film (30), but no adhesivefilm (28), into peripheral foam (16) which is applied to the bottom ofthe bottom of the pane (14) in its edge area, the adhesive film-freeedge area (50) of the film composite (26) is anchored by means of theperforations (52) provided there for passage of the peripheral foamingmass in the peripheral foam (16).
 15. Process as claimed in claim 14,wherein in addition a carrier arrangement (18) for the pane (14) isembedded in the peripheral foam (16) and the film composite (26) isfixed on it before the foaming process.
 16. Process as claimed in claim14 or 15, wherein at least one solar cell (62) is integrated into thefilm composite (26, 60).